Development and comparison of the new index with DAI for evaluating orthodontic treatment need in high caries prevalence community: A diagnostic test study

Abstract

Aim: The aim of this study was to develop an index for evaluating orthodontic treatment need called 'Community Orthodontic Treatment Need Index (COTN)' and to preliminarily compare its accuracy and reliability with Dental Aesthetic Index (DAI). Materials and Methods: This diagnostic test study includes three steps. First and second steps were related to develop the index (COTN) and assessing its accuracy and reliability in dental models. The 110 orthodontic dental models were randomly selected from the pooled dental models of 12-14-year-old children who came for orthodontic screening at the University Orthodontic Clinic. Seven experienced orthodontists assessed orthodontic treatment needs in all 110 dental models (gold standard). Eighty dental models were randomly selected from these 110 models to develop the index by creating algebraic equations using discriminant analysis. Another 30 dental models were evaluated for accuracy and intra-examiner reliability of the two indexes. The last step compared reliability and time consuming of indices in the community. Two examiners assessed 28 schoolchildren aged 12-14 years who were purposively selected using two indices at school. Kappa coefficient, sensitivity, specificity, and paired t test were calculated. Results: COTN contains both anterior and posterior teeth components. It was more likely to have better accuracy and intra-examiner reliability in evaluating orthodontic treatment needs in dental models than DAI (sensitivity + specificity = 1.67 vs. 1.56, kappa = 0.811 vs. 0.689, respectively). Nevertheless, COTN was comparable to DAI for reliability and time consuming when used in the community. Conclusion: This new index (COTN) could be an alternative index for evaluating orthodontic treatment need in high caries prevalence community.